Understood gentlemen, but I think we need to grant Parker Bros. some jounalistic license regarding their small bore marketing campaign.
By 1914, with the cooperation of Bro. Hedderly (editor of Western Field starting in July 1910), Parker had been aggressively promoting small bores for waterfowl for > 5 years; and declared themselves "the pioneer makers in America" of the 20 bore in the May 1916 Forest & Stream
https://books.google.com/books?id=VN1JAAAAYAAJ&pg=PA974&lpg

[Linked Image from photos.smugmug.com]

They were still offering the 20 bore booklet in 1921
July 1921 Outers' Recreation
https://books.google.com/books?id=hns7AQAAMAAJ&pg=PA86&lpg

[Linked Image from photos.smugmug.com]

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